A treatment method in which an intraocular lens (an intraocular contact lens, a posterior chamber phakic intraocular lens) is implanted in an eye of a patient is known for improving the eyesight of the patient. Hitherto, regarding such an intraocular lens, the position of the lens mounted in an eye of a patient is fixed, and thus the lens focuses on an object located at a certain distance from the lens, but does not focus on an object located closer to or farther from the lens than the object.
Therefore, the present inventors have invented an intraocular lens that allows a patient having the intraocular lens mounted therein to adjust the focus by using relaxation/contraction movement of intraocular tissues (a ciliary body, a ciliary sulcus, etc.) (Patent Document 1).